Type-matrix.



(No Model.)

P. T. DODGE.

TYPE MATRIX.

(Application filed N Patented May I4. 190i.

PHILIP T. DODGE, OF WASHINGTON, DISTRICT OF COLUMBIA.

TYPE-MATRIX.

SPECIFICATION formingpart Of Letters Patent N 0. 674,080, dated May 14, 1901. Application filed November 15, 1892. Serial No. 452,083. (No model-1 To all whom, it may concern:

Be it known that I, PHILIP T. DODGE, of \Vashingtomin the District of Columbia, have invented a new and useful Improvement in Type-Matrices, of which the following is a specification.

In the well-known Mergenthaler linotypemachine and in other machines for producing type-surfaces it is customary to employ a series of matrices, which are assembled temporarily in line side by side to produce a line of type characters on molten or plastic material presented thereto. In practice it is found highly desirable to have that portion of the matrix which contains the character or matrix proper as hard as possible; but for many reasons the hardening of the entire matrix is open to objection. The aim of my invention is therefore to produce a matrix in which the matrix proper or any other selected parts shall possess the necessary degree of hardness, while the remaining portions would be of comparatively soft material.

To this end my invention consists in a matrix which is locally hardened.

The local hardening of the matrices may be elfected by various means. If made of soft iron or steel they may be heated at the point containing the character by means of a flame from a blowpipe and then hardened by dropping them into a suitable fluid or by applying cyanid of potassium, or they may be heated by passing a suitable electric current through the portion to be hardened and then hardened by suddenly chilling them in any suitable manner or by the application of cyanid of potassium, as before mentioned.

The local heating by means of an electric current is not claimed as any part of the present invention, but will be made the subject of a separate application. Being made of brass, bronze, or other soft metals, the matrices may be locally hardened by any mode known to persons skilled in the art, or they may be made in the first instance of hard rolled brass or other hard metal and then subjected in any suitable manner to a heating influence, except at the point where the matrix proper is contained, at which point they may be kept cool by the local application of a jet of cold air or cold water or otherwise.

The accompanying drawing represents in perspective a matrix of the form used in the Mergenthaler machine.

A represents the body of the matrix; B, the character or matrix proper indented in one of its edges. The shaded portion 0 surrounding the character represents a relatively hard portion of the matrix.

It will of course be understood that the matrix may be made of any suitable form ex ternally, the only requirement being that the portion in which the character is seated shall be relatively hard.

The construction herein described is advantageous in that the body presents a hard and durable character or matrix proper, one which will not be alfected by the action of the molten metal, and the walls of which are not likely to become Worn, dented, or broken, as in the case of soft-metal matrices. While presenting these advantages, it also presents the advantage of having soft surfaces wherever it is caused to travel in contact with the various parts of the machine, so that the matrices may be used without danger of wearing and destroying the accuracy of said parts. This is particulary advantageous as regards the parts against which the matrices aline at the casting-point and the teeth of the distributer-bar. The construction shown is also advantageous in that it is possible to locally harden the character without danger of twisting or Warping the body of the matrix, as will happen if it is attempted to harden it throughout, and this in consequence of the variation in thickness at difierent points.

In short, the construction herein described gives the great advantages which attend the use of a hardened matrix, while avoiding the many disadvantages which would attend a matrix hardened throughout.

Having thus described my invention, What I claim isl. A linotype-matrix consisting of a single plate of metal with a female character or matrix proper in its edge and distributing-teeth in its top, the metal immediately around said character being hard and the remaining portion relatively soft.

2. As a new article of manufacture a steel linotypematrix in a single piece substantially as shown with distributing-teeth and a female character, the portion immediately around the character or matrix proper, being tempered and hardened in relation to the body of the matrix.

3. As a new article of manufacture, a linotype-matrix having a locally-hardened portion in which the character is situated.

4. A linotype-matrix consisting of comparatively soft steel and having a locally-hardened portion in which the character is situ- IO ated.

In testimony whereof I hereunto set my hand in the presence of two attesting witnesses.

PHILIP '1. DODGE.

Witnesses:

WARREN S. CHASE, W. R. KENNEDY. 

